new_stars: Add a stars shape to a plot

In j-martineau/pj: Element-wise plots by JAM

Add a stars shape to a plot

Description

A star shape is a collection of star polygons using the same subset of locating parameters from among x, y, n, loc, px, py, re, and te. Star polygons are located in plotting regions using bounding rectangles; a concept used in defining function parameters. See the defining bounding rectangles section for details.

Usage

new_stars(
  pj,
  x,
  y,
  n,
  r = NA,
  e = NA,
  a = NA,
  px = 0.5,
  py = 0.5,
  loc = "b",
  region = ".",
  look = NULL,
  mod = NULL,
  name = "."
)

Arguments

pj	an object of class 'pj'.
x	numeric vector giving horizontal location. When x is used in conjunction with px and w these vectors define a fixed horizontal point for each shape. When x is used in conjunction with re, x defines the left edge of the bounding rectangle of each shape.
y	numeric vector giving vertical location. When y is used in conjunction with py and h these vectors define a fixed vertical point for each shape. When y is used in conjunction with te,y defines the bottom edge of the bounding rectangle of each shape.
n	integer vector with values between 3 and 1000, inclusive, indicating the numbers of sides/vertices of each star polygon.
px	NA or a proportion vector defining the location of x as the proportion of the distance from left to right edge of bounding rectangles. Values are generally between 0 and 1, inclusive, however, when they are outside those values, fixed points x will lie outside bounding rectangles.
py	NA or a proportion vector defining the location of y as the proportion of the distance from bottom to top edge of bounding rectangles. Values are generally between 0 and 1, inclusive, however, when they are outside those values, fixed points y will lie outside bounding rectangles.
loc	character vector indicating where the base of each star polygon is located. 'l', 'r', 'b', and 't' indicate left, right, bottom, and top edges of the bounding rectangle, respectively.
region	either character scalar "." to indicate the most recently used region, a positive integer to indicate the ID number of a region (0 indicates the background region), or a character scalar to indicate the name of a region ('bg' indicates the background region).
look	an optional list containing up to four lists specifying looks to apply to the shape. See the using look to make shapes appear section.
mod	an optional list containing up to four lists specifying modifications to apply to the shape. See the using mod to transform shapes section.
name	character scalar indicating a name for the shape. The special value "." indicates that the pj package create a default name for the shape.

Value

pj with the addition of the defined star-polygons.

Defining bounding rectangles

Bounding rectangles can be located in a number of ways. The following shows valid combination of non-NA locating arguments for star polygons:

(x + px) + (y + py) + s

(horizontal anchor) + (vertical anchor) + side length

(x + px) + y + te

(horizontal anchor) + base length + bottom edge + top edge

x + re + (y + px)

left edge + right edge + (vertical anchor)

In addition, star polygons can be squeezed or stretched horizontally and vertically by specifying the location of all four edges of the bounding rectangle as follows:

x + re + y + te)

left edge + right edge + bottom edge + top edge

Argument recycling

The argument set {n, x, y, w, h, re, te, px, py, loc} is recycled.

Bounding rectangles, px, and py

When px is not NA, it represents where the value x is located as a proportion of the distance between the left and right edge of each bounding rectangle. Likewise, when py is not NA, it represents where the value y is located as a proportion of the distance between the bottom and top edge of each bounding rectangle. For example:

• when px = 0.5 and py = 0.5, the center of the bounding rectangle is located at (x, y).

• when px = 0 and py = 0, the bottom left corner of the bounding rectangle is located at (x, y).

• when px = 1 and py = 1, the top right corner of the bounding rectangle is located at (x, y).

• when px = 1/3 and py = 2/3, the point 1/3 of the way from left to right edge and 2/3 of the way from bottom to top edge of the bounding rectangle is located at (x, y).

px and py can be less than 0 or greater than 1, resulting in the fixed point (x, y) being outside the bounding rectangle.

Using look to make shapes appear

By itself, this function simply defines the location of x-y pairs in the assigned region for the specified shape. Various looks can be added to the shape using the look parameter or via the add_ends, add_fills, add_glyphs, add_labels, add_lines, and add_marks functions. Sub-lists of the look argument must be named 'end', 'fill', 'glyph', 'label', 'line', and/or 'mark' to indicate that line end marks, fill colors, glyphs (single characters), labels, lines, and/or point marks be added to the shape.

Using mod to transform shapes

Shapes can be transformed in four ways: dilation, reflection, rotation, and translation/. using the mod argument or the mod_dilate, mod_reflect, mod_rotate, and mod_translate. Sub-lists of the mod argument must be named 'dilate', 'reflect', 'rotate', and/or 'translate' to indicate that a dilation, reflection, rotation, and or translation be applied to the shape.

See Also

Other new_polygons: new_free(), new_polys(), new_regulars()

j-martineau/pj documentation built on March 19, 2022, 5:32 a.m.